鄂尔多斯盆地旦八油田延长组长3储层研究     

许小强  赵进义  郭浩  潘翔 《云南地质》2011,30(1):115-117

三叠系延长组长3储集层灰色细粒长石砂岩储层物性差,属低孔、低渗储层.空隙以粒间孔、溶孔为主,且成岩作用控制孔隙结构.根据岩性、物性特征,把研究区储层分为四类:Ⅰ类好储集层,Ⅱ类较好储集层,Ⅲ类较差储集层,Ⅳ类非储层.  相似文献   

Incentives,social–ecological feedbacks and European fisheries     

H. Österblom  M. Sissenwine  D. Symes  M. Kadin  T. Daw  C. Folke 《Marine Policy》2011

The European Common Fisheries Policy (CFP) has failed to deliver on social, economic and ecological goals. This failure is in part the result of a number of social–ecological feedback mechanisms. The policy is currently undergoing reform, with unknown practical outcomes. Here, relatively successful fisheries policies outside the European Union are reviewed. Through interviews and workshops with scientists, managers and other stakeholders, complemented with literature reviews, practices that can create incentives for long-term sustainability are investigated. The focus is on how the provision of clear and trusted scientific evidence can stimulate defensible decisions, in turn creating incentives for compliance, leading to positive social–ecological outcomes. Despite differences between Europe and the investigated case studies, the prospects of an increased regionalization within the European CFP provides the best starting point for implementing best practice identified in this study.  相似文献   

More than just access to fish: The pros and cons of fisher participation in a customary marine tenure (Padu) system under pressure     

Sarah Coulthard 《Marine Policy》2011

The Padu system of South Asia has received growing attention as an example of customary marine tenure that has survived despite rapid development and change throughout the region’s fisheries. This paper describes the Padu system as it functions at Pulicat lagoon, India, where it has enjoyed decades of legitimacy amongst its members, and has contributed to sustainable fishing. Recently, however, the Padu system has become unstable, driven by pressures of an expanding fishing population, reduced access to fishing grounds and a growing ‘shared poverty’. In spite of this, fisher loyalty to uphold the Padu system remains strong. This raises questions about the broader social, political and cultural meanings of Padu, which extend beyond access to a lucrative fishery. The paper highlights a trade-off between the benefits received through Padu membership at a societal level through collective action, and the individual costs of partaking in ‘shared poverty’, which is inherently distributed unequally amongst fishing families. The paper concludes with a discussion on the future of the Padu system in Pulicat, drawing from evolutionary pathways of other Padu systems in the region. It is suggested that, in the Pulicat case, the high social values attributed to the Padu system, alongside complex power structures, may hinder institutional adaptation.  相似文献   

Contextual factors influencing sustainable fisheries in Mexico     

Alejandro Espinoza-Tenorio  Ileana Espejel  Matthias Wolff  José Alberto Zepeda-Domínguez 《Marine Policy》2011

Sustainable fisheries take into consideration that managed fisheries ecosystems shift over time in response to evolving environmental as well as market and political factors. These contextual forces are especially valuable in understanding developing countries such as Mexico, where the unconsolidated fisheries administration faces productive marine ecosystems but unsustainable fisheries. To recognize the issues that have inhibited the consolidation of a regulatory system for sustainable fisheries, a contextual factor analysis was applied to the co-development of two current policies in the Mexican fishery regime: fisheries and environmental policies. Six historical phases have been identified in which there are few long periods of stability and frequent short periods of radical change that alternate between stable and adverse contextual situations. These short and contrasting contextual situations cause a kind of tug-of-war in Mexican fisheries policy-making. On the one hand, domestic economic, scientific, and technological forces seem to slowly lead toward the consolidation of sustainable fisheries; on the other hand, domestic policies drift from one position to another at other timing than the international fisheries and environmental policies. Although recent crises seem to highlight new periods of radical change in Mexico, they also provide an opportunity to adopt new structural plans to consolidate domestic forces as a basis for long-term strategies.  相似文献   

3-D internal architecture of methane hydrate-bearing turbidite channels in the eastern Nankai Trough, Japan     

Satoshi Noguchi  Naoyuki Shimoda  Osamu Takano  Nobutaka Oikawa  Takao Inamori  Tatsuo Saeki  Tetsuya Fujii 《Marine and Petroleum Geology》2011,28(10):1817-1828

The reservoir architecture of methane hydrate (MH) bearing turbidite channels in the eastern Nankai Trough, offshore Japan is evaluated using a combination of 3-D seismic and well data. On the 3-D seismic section, the MH-bearing turbidite channels correspond to complex patterns of strong seismic reflectors, which show the 3-D internal architecture of the channel complex. A seismic-sequence stratigraphic analysis reveals that the channel complex can be roughly classified into three different stages of depositional sequence (upper, middle, and lower). Each depositional sequence results in a different depositional system that primarily controls the reservoir architecture of the turbidite channels. To construct a 3-D facies model, the stacking patterns of the turbidite channels are interpreted, and the reservoir heterogeneities of MH-bearing sediments are discussed. The identified channels at the upper sequence around the β1 well exhibit low-sinuosity channels consisting of various channel widths that range from tens to several hundreds of meters. Paleo-current flow directions of the turbidite channels are typically oriented along the north-northeast-to-south-southwest direction. High-amplitude patterns were identified above the channels along the north-to-south and north-northeast-to-south-southeast directions. These roughly coincide with the paleo-current flow of the turbidite channels. An interval velocity using high-density velocity analysis shows that velocity anomalies (>2000 m/s) are found on the northeastern side of the turbidite channels. The depositional stage of the northeastern side of the turbidite channels exhibits slightly older sediment stages than the depositional stages of the remaining channels. Hence, the velocity anomalies of the northeastern side of the channels are related to the different stages of sediment supply, and this may lead to the different reservoir architectures of the turbidite channels.  相似文献   

新疆福海第一农场水库浮游植物生态初步研究     

薛俊增  蔡桢  王琼  朱新英  李周永  吴惠仙 《海洋湖沼通报》2011,(1):36-42

于2008年7月(平水期)、10月(枯水期)和次年5月(丰水期)对新疆阿勒泰地区福海县第一农场水库浮游植物进行了生态学调查.共采集到浮游植物8门75种(属),其中绿藻28种、硅藻21种、蓝藻13种、裸藻6种、黄藻2种、甲藻2种、隐藻2种和金藻1种,绿藻和硅藻在种类组成上占明显优势.各期优势种不尽相同:平水期优势种为类颤...  相似文献   

平湖地区ZST构造X井平湖组储层特征研究     

张萍  宋刚练  余学兵 《海洋地质译丛》2011,(2):43-46,81

以平湖地区ZST构造X井区有限的钻井资料为基础,利用岩石铸体薄片、扫描电镜、X-衍射等测试技术手段,对该井区平湖组的岩石学特征、粒度、储层物性等方面开展了系统研究。研究揭示：该储层的岩石类型主要为长石岩屑砂岩,属中孔中渗砂岩储层。平湖组储层物性受沉积环境和成岩作用的双重影响。沉积环境控制储层物性,潮间带和潮下带发育的潮道砂、砂坪是较好的储层;成岩作用对储层物性优劣起主导作用,胶结作用导致储层物性变差,溶蚀作用（长石溶蚀作用）改善了本井平湖组的储层物性。  相似文献   

Seasonal variation in functional phytoplankton groups in Xiangxi Bay, Three Gorges Reservoir     

杨敏  毕永红  胡建林  朱孔贤  周广杰  胡征宇 《中国海洋湖沼学报》2011,(5)

We describe the phytoplankton dynamics and structure in Xiangxi Bay, Three Gorges Reservoir. Samples were collected monthly in the surface waters between August 2007 and July 2008. We identified 10 principle functional groups. C-strategists and S/R-strategists with a wide range of tolerance dominated the phytoplankton assemblage. Seasonal variation was related to water column stability because of changes in hydraulic operation in October, January, and May. Functional group C (Asterionella formosa) and P (Au...  相似文献   

国外海洋渔业准入制度的实践分析   总被引：1，自引：0，他引：1  

唐建业 《广东海洋大学学报》2011,31(2):1-6

捕捞生产的准入是进行海洋渔业资源有效管理的必要条件。综合相关国家渔业管理发展过程,准入制度可能有三种类型:初步准入制度、投入型准入制度和产出型准入制度。准入的对象涉及渔船、渔获及渔具等。从实践经验看,在渔船数量扩展前,建立有效的准入制度的成功概率相对较大;如果现有的捕捞能力已经远超过渔业资源的承载能力时,投入型准入制度虽然还是十分重要,但在削减捕捞能力方面作用有限;产出型准入制度在一些国家的渔业实践中取得了一定的成功,但存在着诸如总可捕量控制、监测与执法等方面的问题。总体上,捕捞权利与捕捞许可证流转等是实施准入制度过程中应给予关注的两个事项。我国可在现行的捕捞许可证与船网工具指标制度的基础上完善我国投入型准入制度,将渔具纳入管理;在条件成熟的情况下,可适当过渡实施产出型准入制度。  相似文献   

密云水库周边山区滑坡泥石流易发区预估   总被引：4，自引：1，他引：3  

宋杨  程维明  柏延臣  万丛  申元村  蒋艳  刘海江 《地理科学进展》2011,30(3):343-351

滑坡、泥石流等地质灾害的易发度主要是地质灾害自然属性特征的体现,它与孕灾环境的各项因子密切相关。这些因子包括地形地貌、流域水文、构造等内部条件因子以及地震、降雨等外部触发因子。为突出反映滑坡及泥石流主导因子的作用,本文参考了许多研究所采用的评价方法和因子选择,重点选取对该地区滑坡及泥石流发生区域分析评价起一定主导作用的、便于研究区域数据资料与空间资料匹配、关系密切的几个指标,包括地形地貌要素(坡度、坡向、坡形、相对高差、地貌类型)、环境要素(植被指数、河网密度、洪水淹没范围)、构造要素(距断层的距离、断层密度、地质岩性),通过对这些因子的敏感性进行分析,采用专家打分方法确定每种要素及因子的权重,借助因子加权叠加办法得出研究区地质灾害易发程度空间分布,用于表示其可能发生的统计意义上的可能性(概率),该研究对于区域地质灾害预防具有一定的适用价值。  相似文献